Reinforced key fob

ABSTRACT

An example key fob assembly includes a circuit board having a plurality of circuits in the keypad having a plurality of coupled buttons closing the plurality of circuits. A reinforcement member secures to a key fob housing between the circuit board and the keypad. The circuit board abuts the reinforcement member.

CROSS REFERENCE TO RELATED APPLICATION

The application claims priority to U.S. Provisional Application No.60/861,524 which was filed on 27 Nov. 2006.

BACKGROUND OF THE INVENTION

This application relates generally to a key fob assembly with aninternal reinforcement member.

Key fob assemblies are known and used to initiate a wide variety offunctions, particularly vehicle functions. Some key fobs include buttonsfor locking and unlocking a vehicle, for example. Vehicle operatorsoften transport the key fob in their pocket or purse when not operatingthe vehicle.

Typical key fobs are exposed to a wide range of outside forces andenvironmental conditions. If the key fob is inadequately supported, someforces, such as those introduced when the key fob is dropped or crushed,can cause severe damage. Key fob manufacturers often require that thekey fobs they manufacture withstand certain loads to avoid high numbersof damaged key fobs. Many key fobs include structures for absorbingloads to ensure that the key fob remains usable after loading.

Key fob buttons move relative to other portions of the key fob.Adequately supporting areas of the key fob near the buttons isespecially difficult because the moveable buttons require adequate areato move, but offer little support. Soft touch buttons are especiallyunsupportive. Accordingly, many key fobs include exposed supportstructures separating adjacent buttons on the key fob. Exposed supportsbetween the buttons complicate the overall key fob design, are notaesthetically pleasing, and are difficult to clean. Exposed supportsrequire space between adjacent buttons, which increases the size of thekey fob.

SUMMARY

An example key fob assembly includes a circuit board having a pluralityof circuits in the keypad having a plurality of coupled buttons closingthe plurality of circuits. A reinforcement member secures to a key fobhousing between the circuit board and the keypad. The circuit boardabuts the reinforcement member.

The example key fob assembly may further include a circuit board havinga plurality of circuits and a keypad having a plurality of coupledbuttons for closing the plurality of circuits. A reinforcement memberhas a portion located between the circuit board and the keypad. An upperhousing engages the circuit board and the lower housing engages theupper housing and the support.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features of the present invention can be best understoodfrom the following specification and drawings, the following of which isa brief description.

FIG. 1 shows a top view of an example key fob assembly.

FIG. 2 shows a sectional view along line 2-2 of the FIG. 1 key fob.

FIG. 3 shows an exploded view of the FIG. 1 key fob.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1 and 2, an example key fob assembly 20 includes akeypad 24 within an upper housing 28. A lower housing 32 secures to theupper housing 28 to secure a reinforcement member 36 and a circuit board40 within the key fob 20.

In this example, the reinforcement member 36 directly abuts the circuitboard 40 at 38. A plurality of apertures 44 within the reinforcementmember 36 permit snap domes 48 extending from individual buttons 52 orswitches on the keypad 24 to contact portions of the circuit board 40.Contacting a circuit 78 on the circuit board 40 with one of the snapdomes 48 closes the circuit 78.

The example key fob 20 includes various buttons 52, such as a lock 52 aand an unlock switch 52 b, for controlling vehicular functions. The keyfob 20 further includes a slidably switch 60 for releasing a valet key,for example.

As shown in FIG. 3, the upper housing 28 includes an opening 64 forreceiving the keypad 24. The upper housing 28 is a polymer materialmolded as a single piece. A ridge 68 around the opening 64 contacts alip 72 on the keypad 24 to limit movement of the keypad 24 away from theremaining portion of the key fob assembly 20.

In this example, the buttons 52 within the keypad 24 are coupledtogether and molded as a single membrane. The example buttons 52 aresoft touch switches, which are formed of a softer polymer material thatthe surrounding the upper housing 28. A plurality of molded ribs 74 ordepressions within the keypad 24 separate the buttons 52. The ribs 74provide tactile feedback to a key fob operator to facilitatedistinguishing between adjacent buttons 52 within the keypad 24. Theribs 74 provide separation between adjacent buttons 52 and facilitatemovement of the buttons 52, especially soft touch switches. The ribs 74require less packaging space than former external supports, whichreduces the packaging area required for buttons 52 and the keypad 24.

Molding the keypad 24 from a single sheet of material minimizes gapswithin the key fob 20. For example, as the ribs 74 are molded within thekeypad 24, there is no path or opening from the exterior of the keypad24 to the interior of the key fob 20 through adjacent buttons 52. In theexample key fob 20, paths or openings are limited to the perimeter edgesof the keypad 24 in the assembled position, such as the area near theopening 64 in the upper housing 28, or the interface between the upperhousing 28 and the lower housing 32. Limiting paths to the interior ofthe key fob assembly 20 decreases the propensity for leaks and moistureentering the key fob 20, which protects components contained therein.

The undersides of the buttons 52 include associated snap domes 48extending away from the key pad 24. Apertures 44 within thereinforcement member 36 permit the snap domes 48 to extend from thekeypad 24 toward a respective circuit 78 on the circuit board 40, whichis a printed circuit board in this example. Contacting one of thecircuits 78 with one of the snap domes 48 closes that circuit. As known,closing a circuit may initiate a variety of functions, includingvehicular functions such as locking or unlocking a car door. Otherexamples may include extensions such as poly domes instead of snap domes48.

Other than the apertures 44, the reinforcement member 36 extends acrossthe key fob 20. In this example, the reinforcement member 36 is moldedas a single structure. Portions of the keypad 24, such as the ribs 74,rest directly on the reinforcement member 36. Supporting the keypad 24in this manner strengthens the areas of the key fob 20 near the buttons52 without limiting movement of the buttons 52 or substantiallydisrupting the continuity of the keypad 24.

The opposing side of the reinforcement member 36 directly contactsportions of the circuit board 40, which similarly strengthens the keyfob 20. As known, strengthening the key fob 20 enhances performance anddurability of the key fob 20 when loaded. To enhance the support of thecircuit board 40, the reinforcement member 36 may include a flange 82extending from the reinforcement member 36 for receiving the circuitboard 40 and protecting the edges of the circuit board 40. In thisexample, the flange 82 also maintains the position of the circuit board40 relative to the reinforcement member 36.

The upper housing 28 and the lower housing 32 attach with snap tabs inthis example. Securing the key fob assembly 20 secures the keypad 24,the reinforcement member 36 and the circuit board 40 within the upperhousing 28 and the lower housing 32. Other examples may include weldingor heat staking the upper housing 28 to the lower housing 32, as well aswelding, heat staking, or snapping the reinforcement member 36 to theupper housing 28, the lower housing 32, or both. When the upper housing28 is secured to the lower housing 32 the ridge 68 around the opening 64clamps the keypad 24.

While the preferred embodiment of this invention has been disclosed, aworker of ordinary skill in the art would recognize that certainmodifications would come within the scope of this invention. For thatreason, the following claims should be studied to determine the truescope and content of this invention.

1. A key fob assembly, comprising: a circuit board having a plurality ofcircuits; a keypad having a plurality of coupled buttons operative toclose said plurality of circuits; and a reinforcement member secured toa key fob housing between said circuit board and said keypad, saidreinforcement member abutting said circuit board.
 2. The key fobassembly of claim 1, including an upper housing and a lower housing,said reinforcement member and said lower housing holding said circuitboard.
 3. The key fob assembly of claim 1, wherein said reinforcementmember surrounds a perimeter edge of said circuit board.
 4. The key fobassembly of claim 1, wherein one of said plurality of coupled buttonsincludes an extension for contacting one of said plurality of circuitsthrough at least one aperture within said reinforcement member.
 5. Thekey fob assembly of claim 1, wherein said reinforcement member contactssaid keypad and said circuit board.
 6. The key fob of claim 1 whereinultrasonic welding secures said support.
 7. The key fob of claim 1including a snap dome for communicating movement of one of saidplurality of coupled buttons to one of said plurality of circuits. 8.The key fob of claim 1 wherein said keypad comprises a soft-touchkeypad.
 9. The key fob of claim 1 wherein said keypad comprises acontinuous sheet of material.
 10. The key fob of claim 1 wherein saidplurality of coupled buttons are molded together.
 11. The key fob ofclaim 1 wherein said keypad and said housing cover said support.
 12. Thekey fob of claim 1 wherein said circuit board is a printed circuitboard.
 13. A key fob assembly, comprising: a circuit board having aplurality of circuits; a keypad having a plurality of coupled buttonsfor closing said plurality of circuits; an upper housing; a lowerhousing for engaging said upper housing; and a reinforcement member atleast partially located between said circuit board and said keypad, saidreinforcement member and said lower housing holding said circuit board.14. The key fob assembly of claim 13, wherein said reinforcement memberdirectly contacts said circuit board.
 15. The key fob assembly of claim13, wherein said reinforcement member surrounds a perimeter edge of saidcircuit board.
 16. The key fob assembly of claim 14, wherein thereinforcement member extends closer to the perimeter of the key fob thanthe circuit board.